Many users experience problems sending and receiving
via DCC using mIRC. There are a variety of reasons for these problems, some
of which are easily resolved and others not.

DCC Receive Problems

These are the easiest to resolve. There are
only a few reasons you may not be able to receive a file from another person
on IRC.

I. Symptom: You never even see the DCC send.

Four
possible causes for this.

A.) You do not have the file extension e.g. *.mp3 added
to the file types NOT to ignore under FILE >> OPTIONS >> DCC >>
FOLDERS. If you look in your status window you will see a msg stating that the
DCC was rejected...

DCC Send from murf rejected
(kne100tx.exe, file type ignored)

The resolution is to disable
the ignore totally (not recommended for inexperienced users) or just add the
filetype to the list.

NOTE: this feature was added
in mIRC v5.7 and there are some variations in how this feature works from v5.7
to v5.9

D.) CTCP
event handling is off. Type: /ctcps on in any open window to
turn it on.

II. Symptom: You see the DCC send but get an error "You
do not have permission to open this file."

This is because you cannot
write the file out to disk. This could be because the disk is full or because
you do not have permission to write to that directory. Try saving to a different
directory.

To change the default save
locations, look under FILE >>OPTIONS >> DCC >> FOLDERS and
edit as needed in the 'DCC Get Folders' drop down menu.

III. Symptom: You get the error "Unable
to connect"

This is the senderís problem.
See below.

DCC Send Problems

When you initiate a DCC send or chat, you send
a CTCP to the person you are DCCing with your IP information and then open a
port to listen for their reply. The receiver must then be able to find the IP
address and port you are listening on. Only when you receive the acknowledgement
back from the person receiving, is the DCC send connection established.

Therefore DCC send problems have a single root
cause. The receiver cannot reach your system on the appropriate port. However,
there are a variety of reasons for this. Since more and more people have increasingly
complex home networks, it is not possible to describe resolutions to every issue
in detail.

Here are the solutions to the most common problems:

Symptom: All send problems have the same symptom; the receiver simply gets
an "Unable to Connect" error message. From your end it appears as
though the DCC was never acknowledged.

There are two general cases,

∑Your IP is set incorrectly in mIRC

∑Your IP is set correctly but you still
can't DCC send

You can determine which is your problem by typing
the following commands...

/dns your_nick

//echo -a $ip

NOTE for cable users: It is possible that /dns
may not work correctly for you, try /userip your nick instead.)

The results from this should match. The dns
results will show up in the status window and will look something like...

*** Looking up cc388468-b.mcmb1.mi.home.com
-- ***

Resolved cc388468-b.mcmb1.mi.home.com
to 65.7.51.139

...Now typing //echo -a $ip should return in
the active window...

65.7.51.139.

Solution for Mismatched IP Addresses:

Previously, the most common
DCC send problem was mIRC not detecting the correct IP address for your system.
MIRC has gotten much better at detecting the correct IP address and this problem
is far less common. Therefore your first step should be to make sure you are
running the latest version of mIRC. If the problem persists, it is usually related
to network configuration issues and is not resolvable without some reconfiguring
of the network.

Try the following steps depending
on which version of mIRC you are running...

For mIRC v5.7 and
above...

1.Type: /localinfo
-u in any open window

For mIRC v5.6x...

1.Disconnect

2.Go to FILE >> OPTIONS >> CONNECT >>LOCAL
INFO.

3.Clear the local host\IP address,

4.Check always get local host.

5.Select the server method

6.Reconnect.

For older mIRC versions, upgrade,
but failing that...

1.Disconnect

2.Find the local info under the File menu

3.Clear the local host\IP address

4.Check always get local host

5.Select the server method

6.Reconnect.

Now check your IP again, if
the results match you are hopefully fixed. If not, you are probably on a LAN
and you cannot fix your DCC send without assistance from the network administrator.

Solutions when IP Addresses Match:

I.) You (or your company) are running a firewall/proxy.
These block attempts at inbound connections, itís their
job. This effectively kills DCC sends unless you configure them correctly. If
you have set these up at home, then you will need to figure out how to open
the DCC ports. If you are at work or school, you will have to bribe your network
admin to open the ports. MIRC defaults to 1024~5000 for DCC ports, but this
can be set to anything and if you have to open ports on your firewall, a smaller
range is advisable.

II.) You are using a Linksys/Netgear/Other home DSL router.
This equipment is essentially a
firewall and has the same effect of stopping attempts at inbound connections.
Here, too you will have to figure out how to open individual ports. For the
Linksys BEFSR41 or 11 try these steps:

NOTE: Be aware that this workaround
turns off the firewall feature of your router and is not the best solution.
Learning how to forward individual ports is the best solution (Check the help
for Virtual Servers if your documents say nothing about Port Forwarding).

III.) You are connection sharing. If you use connection sharing (Wingate, ICS) it is possible
to get DCC send working. A tutorial for this can be found at, http://www.borg.com/~chuck/

IV.)You are running WindowsXP. WindowsXP has a built-in
firewall that unless it is configured or disabled, will prevent DCC sends.
Right click My Network Places->properties->Right click connection->properties->advanced
tab->uncheck Internet Connection Firewall. A tutorial with pictures can be
found at http://toidyman.net/xp-dcc/5.htm

Final
Note:

If you made it this far and
have no clue what you just read, don't feel bad. There are many solutions available
to the home user that are, by design, simple to install. However, the art of
network configuration is never simple, you should contact your network administrator,
ISP or an online help channel, such as #help.